NASA's X-43A Proves Hypersonic Scramjet Flight

NASA's second X-43A hypersonic research aircraft flew successfully today, the first time an airbreathing scramjet powered aircraft has flown freely.

The unpiloted vehicle's supersonic combustion ramjet, or scramjet, ignited as planned and operated for the duration of its hydrogen fuel supply, which lasted about 10 seconds. The X-43A reached its test speed of Mach 7.

"It's been a great, record-breaking day," said Larry Huebner, NASA Langley Research Center's Hyper-X propulsion lead. "We achieved positive acceleration of the vehicle while we were climbing, and maintained outstanding vehicle control. This was a world-record speed for air-breathing flight," Huebner said.

The flight, originating from NASA's Dryden Flight Research Center, began at 12:40 p.m. PST, as NASA's B-52B launch aircraft carrying the X-43A lifted off the runway. The X-43A, mounted on a modified Pegasus booster rocket, was launched from the B-52B just before 2 p.m. The rocket boosted the X-43A up to its test altitude of about 95,000 ft. over the Pacific Ocean, where the X-43A separated from the booster and flew freely for several minutes following scramjet engine operation, in order to gather aerodynamic data.

"Today was a grand-slam in the bottom of the 12th," said Joel Sitz, NASA Dryden Flight Research Center's X-43A project manager. "It was fun all the way to Mach 7. We separated the research vehicle from the launch vehicle, as well as separating the real from the imagined," Sitz said.

NASA's Langley Research Center, Hampton, Va., and Dryden Flight Research Center, Edwards, Calif., jointly conduct the Hyper-X program. ATK GASL (formerly MicroCraft, Inc.) in Tullahoma, Tenn., built both the vehicle and the engine, and Boeing Phantom Works in Huntington Beach, Calif., designed the thermal protection and onboard systems. The booster is a modified Pegasus rocket built by Orbital Sciences Corp. Chandler, Ariz.